Not all home heating fuels are created equal. Here's what it would cost to heat the average home in the Northeast with oil, natural gas, electricity, and propane, as forecast by the Energy Information Administration (EIA):

The solar-powered plane, scheduled to fly around the world in 2015, travels only 30 miles per hour and will have to stay aloft 20 days, even at night. The solar-powered plane is the brainchild of Bertrand Piccard, the first person to circumnavigate the globe in a hot air balloon.

Scientists have designed an energy-efficient light of plastic packed with nanomaterials that glow. The shatterproof FIPEL technology can be molded into almost any shape, but still needs to prove it's commercially viable.

Nations spend more than $500 billion to keep fossil fuel prices low, which is popular with voters but harms the climate. Removing fossil-fuel subsidies would lower carbon emissions by more than 10 percent by 2050, the OECD calculates.

President Barack Obama is facing pressure from all sides concerning the fate of the Keystone XL, a pipeline that would stretch from Canada through the Midwestern US in order to easily transport crude from Alberta’s oil sands to refineries in Texas.

US Senate voted Wednesday to restore the Defense Department's ability to buy biofuels. As the largest petroleum user in the world, the US military says its dependence on oil is a national security threat.

One big reason the US will become nearly energy self-sufficient by 2035 is increased energy efficiency, says Fatih Birol, chief economist at the International Energy Agency. Aggressive energy efficiency policies could yield even bigger gains.